Driveline whine in 3rd gear

[Rocket Power]

I have a 86 442 and I'm having a bit of a problem. When I'm driving down the street there is a whine coming from somwhere. It stops when I let off the gas and I can't hear it if I hammer on it. It is most noticeable in 3rd gear while cruising at light throttle. Anyone have any ideas? Is it my tranny or rear diff? I just changed the u-joints, rear bearings and seals. Could it be the inner bearings for the diff? I hope it's the tranny and not the diff. I'm dropping an olds 350 and I know the tranny won't last very long but the diff better. I have the stock 3.73's if that makes any differance. Thanks

Adam
86 442

 

[Hi-psi]

Symptons sound like it would be noise from the ring & pinion in the rear.

 

[1FASTV6]

Me 2....

I am also getting it. I was told it was the ring and pinion and the maybe the axle bearings.

Artie

 

[ULYCYC]

Sounds like a pinion bearing to me. Put it up on a lift and run up to 3rd gear. You will hear where is coming from.

 

[Renthorin]

Something similar

I have a humming that occurs around 50 mph. I thought it might be the trans, driveshaft, diff....you name it.

Turned out to be a slightly bent rear rim. Took my tires to the local tire butchers and on the balance machine I could see it.

Might try that.

 

[Rocket Power]

Re: Something similar

Originally posted by Renthorin
I have a humming that occurs around 50 mph. I thought it might be the trans, driveshaft, diff....you name it.

Turned out to be a slightly bent rear rim. Took my tires to the local tire butchers and on the balance machine I could see it.

Might try that.

I had crappy tires that vibrated on there but it stopped when I let off the gas. By pinion bearings you guys mean the ones holding the carrier up right?(one on each side) How hard are these to change? Can I screw the gears if I do those bearings wrong? I might get some of the inner bearings and throw them in before spring, then it will have all new bearings.

 

[77 cruiser]

If any of the above ideas don`t work you may want to check U-joint angles, back of trans could be too low.

Jim

 

[1971OLDS]

Sounds like ring and pinion to me. If you don't have a lift available. Have someone drive your car and sit in the back seat. If it's the rear it will definately be louder back there and you might feel a vibration back there.

To get a rear rebuilt isn't a big deal. It's alot cheaper than having a trans rebuilt. If you have the tools and the patience it isn't all that difficult to do yourself. A new set of gears will run about $150 and then some time to install them.

Just to make a small comment about how your 200-r4 holding up against the 350. I can guarantee you that if you have it done right it will hold. I have one in my 71 olds with a 455 in front of it. It holds up just fine and allowed me to put 4:11 gears in the rear and still run 2800 rpm's at 75 MPH. Just a side thought. The key is pay the money and have it built right. I suggest Bruce. It looks like alot of money but trust me by the time you have the local shop do it and they re do it and re do it until it is right you would have spent the same amount of money.

Later and good luck. Let the board know what the final outcome is.

Brian